(1) Field of the Invention
This invention relates to the automobile repair and maintenance and more particularly to front-wheel alignment for automobiles having MacPherson strut front-wheel suspension.
(2) Description of the Related Art
In recent years many, if not most, automobiles use a unit body. By this it is meant that the body of the automobile is also the frame of the automobile and the ground engaging wheels are supported by the body. In such a construction, the MacPherson strut has become widely used. The main support of the front wheel is the MacPherson strut which extends from the top of the wheel well (sometimes called the tower) to the stub shaft or spindle of the wheel. Many automobiles with the MacPherson struts have no means for adjusting the top of the strut in the event of mis-alignment which occurs as a result of wear or abuse of the vehicle. This problem has been recognized.
Wilkerson in U.S. Pat. No. 4,213,631 suggested as a solution that the automobile be manufactured with the strut attached to the body of the automobile at the top of the wheel well by a plate having four symmetrical bolt holes. The plate would have an eccentric hole to receive the top of the strut assembly including the spring. The plate could be attached in any one of four positions so that the hole and thus the top of the strut assembly could be moved to any one of the four positions. Another plate would be provided with a hole in another eccentric position and therefore it could be attached to adjust the plate in any one of four existing positions. The entire top of the strut assembly could be adjusted in any one of eight different positions by the use of one or the other plates.
Ferman et al, U.S. Pat. No. 4,817,984 discloses a design which has a plate which is clamped in place so that it can be rotated. Therefore, with an eccentric hole in the plate, the top of the strut assembly including spring can be rotated to any position along the circle described by the center of the eccentric hole as the plate is rotated.
Also at the time of filing this application, the applicants were aware of the following U.S. Pat. Nos.
4,026,578 : Mattson PA1 4,733,884 : Pettibone PA1 4,650,208 : Mason PA1 4,618,162 : Specktor
The applicants do not consider the above U.S. Patents to be as pertinent as the two specifically discussed above, however reference is made to them herein because it was believed that the examiner would consider them of interest.